Klebsiella pneumoniae treated conservatively: case report and review AbstrAct

Transcription

Klebsiella pneumoniae treated conservatively: case report and review AbstrAct
CASO CLÍNICO
Klebsiella pneumoniae Spinal Epidural Abscess
treated conservatively: case report and review
Filipe Araújo1,3, Célia Ribeiro1, Inês Silva1, Patrícia Nero1,2, Jaime C. Branco1,2
ACTA REUMATOL PORT. 2012;37:260-263
AbstrAct
other spinal instrumentation) but also to a better and
earlier diagnosis1,2. Pathogens can access the spine
through haematogenous spread from a distant focus
(the predominant route), direct external inoculation or
contiguous infected tissues (with SEA complicating 5-18% of spondylodiscitis through this latter mechanism)3. Staphylococcus aureus is the leading agent of
both spondylodiscitis and SEA in developed countries,
with Klebsiella pneumoniae being an uncommon one.
In the presence of SEA, aggressive treatment combining surgical drainage and systemic antibiotics
should be performed in the overwhelming majority of
cases, since serious infectious and neurological complications can occur4. Medical treatment alone might
be used in exceptional circumstances.
The authors report the case of a K. pneumoniae lumbar spine spondylodiscitis with SEA managed conservatively.
Spinal infections are rare but potentially life-threatening disorders. A high level of clinical suspicion is
necessary for rapid diagnosis and treatment initiation.
The treatment combines both antibiotics and surgical
intervention in the vast majority of cases. The authors
report the case of a 84-year old female patient with a
three week history of persistent lumbar back pain radiating to both thighs following a lower respiratory tract
infection. She had lumbar spine tenderness but no neurological compromise. Her inflammatory markers were
elevated and lumbar spine magnetic resonance imaging
revealed L4-L5 spondylodiscitis with spinal epidural
abscess. Blood cultures isolated Klebsiella pneumoniae
and, since she was neurologically stable, conservative
treatment with two-week intravenous gentamicin and
eight-week intravenous ceftriaxone was initiated with
positive inpatient and outpatient evolution.
clInIcAl cAse
Keywords: Klebsiella pneumoniae; Spondylodiscitis;
Epidural abscess.
An 84 year-old female caucasian patient presented to
our Emergency Department with a three-week history
of persistent lumbar back pain that radiated to both
thighs. She had no fever, no weight loss or night sweats
and no history of trauma. No lower limb neurological
complaints were reported. One week prior to the beginning of her lumbar back pain she was diagnosed
with a lower respiratory tract infection and was treated
with amoxicillin and clavulanic acid (875+125 mg
b.i.d.) for ten days on an outpatient basis with improvement of her respiratory complaints.
The patient had controlled hypertension for 10
years, currently treated with diltiazem (60 mg q.d.);
peptic ulcer diagnosed 15 years earlier, currently treated with lansoprazol (30 mg q.d.); she had no history
of drug reactions and no tobacco, alcohol or illicit drug
abuse was reported.
IntroductIon
Spinal infections are severe but rare disorders. Spondylodiscitis and spinal epidural abscess (SEA) are two of
the most important spinal infections and their incidence has been rising in the past decades owing to the
growing number of patients with predisposing risk factors (such as diabetes mellitus, alcoholism, immunodeficiency, intravenous drug use, neurosurgery and
1. Department of Rheumatology, Centro Hospitalar de Lisboa
Ocidental, Hospital de Egas Moniz
2. CEDOC, Faculdade de Ciências Médicas, Universidade Nova de
Lisboa
3. Institute of Microbiology, Faculdade de Medicina da
Universidade de Lisboa
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Filipe ArAÚjo e col
FIGure 1. (A) Lumbar spine radiograph by the time the
patient presented to our Emergency Department, showing early
signs of spondylodiscitis: narrowing of the L4-L5 intervertebral
disk space (arrow); (B) Lumbar spine radiograph after 8-week
treatment with Ceftriaxone and 2-week treatment with
Gentamicin showing narrowing of disk space and destruction
of the superior endplate (arrowhead), towards vertebral fusion
Physical examination revealed normal blood pressure, pulse and respiratory rate. The temperature was
36.2ºC. The skin was pale and she had no cyanosis.
Chest and abdomen examination showed no abnormalities. Negative renal Murphy sign bilaterally. She
had lumbar spine tenderness but with normal gait and
normal lower limb rheumatologic examination including negative Laségue sign. Neurologic examination was unremarkable for lower limb motor or sensory function loss. Lower limb reflexes were also normal.
Initial laboratory test results revealed hemoglobin
level of 9.1 g/dL, MCV 92.8 fl, MCHC 32.9 g/L,
7.8x109 leucocytes with 77.7% neutrophils, 331x109
platelets/L, normal reticulocyte count, iron 25 µg/dL
(N: 37-170), ferritin 100 ng/mL (N: 13-264), TIBC
217 µg/dL (N: 250-450), normal folic acid and B12 vitamin levels. Kidney and liver function tests were
within normal range. Serum protein electrophoresis
revealed no abnormalities. C-reactive protein (CRP)
level was 13.9 mg/dL and erythrocyte sedimentation
rate (ESR) was 79 mm/h. Normal urinalysis. Chest radiograph and electrocardiogram were unremarkable.
Lumbar spine radiograph showed osteophytosis and a
slight narrowing of the L4-L5 intervertebral disk space
(Figure 1). Renal ultrasound revealed normal sized and
shaped kidneys with no signs of calculi or pyelonephritis.
FIGure 2. Sagittal T2-weighted MRI showing L4-L5
spondylodiscitis complicated by anterior epidural abscess
(arrow) and soft tissue phlegmon (arrowhead)
The patient was admitted with the clinical suspicion of spondylodiscitis.
Three days after admission the patient started daily
fever spikes usually in the afternoon (maximum tympanic temperature of 38.8ºC) that were easily resolved
with cooling measures and paracetamol. Since she was
clinically stable it was decided to postpone antibiotic
empiric therapy until all microbiological samples were
obtained. Thoracic and lumbar spine magnetic resonance imaging (MRI) confirmed L4-L5 spondylodiscitis and a voluminous epidural abscess with
moderate dural sac compression. It was also visible a
moderate sized soft-tissue phlegmon (Figure 2). Blood
cultures isolated Klebsiella pneumoniae. Purified protein derivative (PPD) test was non-reactive. Mycobacterium-specific blood cultures and Brucella spp. polymerase chain reaction were both negative. Urine cultures were sterile. The patient was submitted to CT-guided intervertebral disc biopsy that was negative
for causative organisms and showed only cartilaginous
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KlebsiellA pneumoniAe spinAl epidurAl Abscess treAted conservAtively: cAse report And review
tissue on histologic examination. After discussion with
the Department of Neurosurgery it was decided that
conservative treatment would be appropriate and the
patient started ceftriaxone 1000 mg b.i.d. and gentamicin 80 mg q.d., both intravenously. She was treated with Gentamicin for two weeks with close antibiotic-level and kidney-function monitoring. Fever subsided 6 days after starting the antibiotic treatment and,
at week 2 of treatment, control lumbar spine MRI
showed persistence of L4-L5 spondylodiscitis but
epidural abscess size reduction. At this time CRP level
was 5.9 mg/dL. The patient completed 8 weeks of
Ceftriaxone. By the time of discharge she reported
significant pain improvement. Her CRP was negative
and lumbar spine MRI continued to show positive evolution of both spondylodiscitis and SEA.
(radiculopathy); stage 3, motor weakness, sensory
deficit and bowel or bladder dysfunction; stage 4,
paralysis3,4. This patient was included in the second
stage.
The absence of leukocitosis is not an unusual finding since it is present in only one third of spondylodiscitis1 and two thirds of SEA4. ESR and CRP, both
elevated, are sensitive but not specific of spinal infections. All biological samples should be obtained previously to the beginning of antibiotics, although treatment should not be withheld in severe cases, for instance, sepsis6. The performed CT-guided intervertebral disc biopsy showed normal cartilaginous tissue
and normal cultures, which suggests that it didn’t reach
the site of infection. Since there were already positive
blood-cultures for K. pneumoniae, no second percutaneous or surgical intervertebral disc biopsy was executed. MRI is the imaging method of choice for
spondylodiscitis and SEA for its excellent sensitivity
and specificity1-6.
It is consensual that, in the presence of a SEA and
due to the possible adverse outcomes, surgical drainage combined with systemic antibiotics is the treatment
of choice4. Posterior decompression (laminectomy) is
reserved for isolated posterior SEA, whereas anterior
decompression should be performed in anterior SEA
with or without vertebral body and disc involvement3.
However, there are a few exceptions to this invasive
approach. If surgery is declined by the patient or is
contraindicated because of elevated operative risk, if
the paralysis is present for more than 36 hours or if
the SEA is panspinal, medical treatment alone is
recommended4. Patients not suffering from severe loss
of spinal cord or cauda equina function may also qualify for conservative treatment as long as a microbial
cause is identified and frequent clinical, laboratorial
and imaging evaluation is performed2. The patient was
included in the second stage of Heusner classification.
Since she was neurologically stable and had positive
blood-cultures for K. pneumoniae, conservative therapy with antibiotic treatment alone was used based on
the antibiotic sensitivity test. One of the most controversial issues is the duration of this treatment because
no uniform recommendations exist for spinal infections. A minimum of 6 weeks of intravenous antibiotic seems appropriate in the published literature for
concomitant SEA and spondylodiscitis. The treatment
should be prolonged for a period varying from 8 to 12
weeks2,3,8.
The authors decided to report this case because, to
dIscussIon
Spondylodiscitis represents 3-5% of all cases of osteomyelitis1. Blood-borne spondylodiscitis can originate
from the genitourinary tract (17%), infectious endocarditis (12%), skin and soft tissue (11%), intravascular
devices (5%), gastrointestinal tract (5%), respiratory
tract (2%) and the oral cavity (2%)5. Gram-negative
bacteria are the third leading cause of pyogenic spondylodiscitis in developed countries with Escherichia coli
as the main pathogen. K. pneumoniae is responsible for
about 1.8% of pyogenic spondylodiscitis6 and 1% of
SEA2. Once the infection is settled in the intervertebral
disc and vertebral bodies, it may originate local and
systemic complications. Locally, it may spread to the
myofascial tissues and epidural space or it may destroy
the vertebral body and disc causing spinal instability
and deformity7. Systemically, it can degenerate into uncontrolled sepsis.
In this case, the diagnosis of spondylodiscitis was
suspected since a temporal relationship could be established between the lower respiratory tract infection
and the beginning of a persistent and refractory lumbar back pain. This clinical suspicion is of outmost importance since the majority of spinal infections is confounded with spine degenerative disease and is consequently misdiagnosed at an early stage. Classical
symptoms of both spondylodiscitis and SEA were present: spinal pain, fever and neurologic signs (radiculopathy)1,2,4. Heusner proposed in 1948 a staging system for patients with SEA: stage 1, back pain; stage 2,
nerve-root pain radiating from the involved spinal area
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Filipe ArAÚjo e col
our knowledge, this is the first reported K. pneumoniae
lumbar SEA originating from the respiratory tract that
was treated conservatively. In the existing literature
there are three reported cases of K. pneumoniae SEA
originated from the gastrointestinal tract, two of them
treated with surgical intervention9,10,11. In a recent review of 12 patients from Taiwan with Gram negative
SEA, K. pneumoniae and Salmonella spp. were the most
frequent causative pathogens (three cases each) and
the majority were treated with a combination of
surgery and antibiotics12.
In conclusion, patients should be carefully selected
for isolated conservative treatment based upon their
clinical and neurological status and frequent clinical
and imaging evaluation should be performed.
3. Quiñones-Hinojosa A, Jun P, Jacobs R, Rosenberg W, Weinstein
P. General principles in the medical and surgical management
of spinal infections: a multidisciplinary approach. Neurosurg
Focus 2004; 17: 1-14.
4. Darouiche R. Spinal Epidural Abscess. New Engl J Medicine
2006; 355: 2012 – 2020.
5. Mylona E, Samarkos M, Kakalou E, et al. Pyogenic vertebral
osteomyelitis: a systematic review of clinical characteristics. Semin Arthritis Rheum 2009; 39: 10–17.
6. Skaf G, Domloj N, Fehlings M, et al. Pyogenic spondylodiscitis: An overview. Journal of Infection and Public Health. Published Online First 19 Feb 2010, doi:10.1016/j.jiph.2010.
01.001.
7. Hsieh P, Wienecke R, O’Shaughnessy B, Koski T, Ondra S. Surgical strategies for vertebral osteomyelitis and epidural abscess.
Neurosurg Focus 2004; 17: 1-6.
8. Grewal S., Hocking G., Wilsmith J. Epidural abscesses. British
Journal of Anaesthesia, Published Online First January 23,
2006, doi:10.1093/bja/ael006.
9. Kuramoshi G, Takei SI, Sato M, Isokawa O, Takemae T, Takahashi A. Klebsiella pneumoniae liver abscess associated with
septic spinal epidural abscess. Hepatol Res. 2005; 31: 48-52.
10. Barton E, Flanagan P, Hill S. Spinal infection caused by ESBLproducing Klebsiella pneumoniae treated with temocillin. J Infect 2008; 57: 347-349.
11. Hsieh MJ, Lu TC, Ma MH, Wang HP, Chen SC. Unrecognized
cervical spinal epidural abscess associated with metastatic Klebsiella pneumoniae bacteremia and liver abscess in nondiabetic
patients. Diagn Microbiol Infect Dis 2009; 65: 65-68.
12. Chi-Ren Huang, Chen-Hsien Lu, Yao-Chung Chuang, et al. Clinical characteristics and therapeutic outcome of Gram-negative bacterial spinal epidural abscess in adults. Journal of Clinical Neuroscience 2011; 18: 213–217.
corresPondence to
Filipe Araújo,
Serviço de Reumatologia, Hospital Egas Moniz,
Rua da Junqueira, 126
1349-019 Lisboa, Portugal
E-mail: flipar@msn.com
reFerences
1. Gouliouris T, Aliyu S, Brown N. Spondylodiscitis: update on
diagnosis and management. J Antimicrob Chemother 2010;
65: 11-24.
2. Sendi P, Brezenger T, Zimmerli W. Spinal epidural abscess in clinical practice. Q J Med 2008; 101: 1- 12.
PArAdIGm shIFt III
Óbidos, Portugal
20 Outubro 2012
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